Seal structure for a rotary valve compressor

Abstract

A variable displacement compressor includes a rotary valve coupled to a drive shaft of the compressor and configured to selectively permit fluid communication between a suction chamber and cylinders of the compressor. An annular seal is disposed adjacent the rotary valve and engages at least a portion of a wall defining the suction chamber and a surface of the rotary valve.

What is claimed is: 
     
         1 . A rotary valve assembly for controlling a supply of refrigerant gas to cylinders in a variable displacement compressor, the rotary valve assembly comprising:
 a rotary valve configured to selectively permit fluid communication between a suction chamber and cylinders of the compressor; and   an annular seal disposed adjacent the rotary valve and having a diameter corresponding to a diameter of the rotary valve.   
     
     
         2 . The rotary valve assembly of  claim 1 , wherein the seal has a substantially rectangular cross-sectional shape. 
     
     
         3 . The rotary valve assembly  claim 1 , wherein the seal has an outer surface, the outer surface having a bevel formed therein, wherein the bevel has a bevel angle of about 70 degrees. 
     
     
         4 . The rotary valve assembly  claim 1 , further comprising an urging member disposed adjacent the seal and configured to urge the seal towards the rotary valve. 
     
     
         5 . The rotary valve assembly  claim 1 , further comprising at least one position tab extending laterally outwardly from an outer surfaee of the seal. 
     
     
         6 . The rotary valve assembly  claim 5 , wherein the position tab has a shape corresponding to a shape of a recess formed in a wall forming the suction chamber of the compressor. 
     
     
         7 . The rotary valve assembly of  claim 1 , wherein the seal is formed from a PEEK material. 
     
     
         8 . A variable displacement compressor, comprising:
 a cylinder block having a plurality of cylinders annularly formed therein and a centrally formed aperture, a plurality of pistons received within the cylinders;   a rear head disposed adjacent one end of the cylinder block, the rear head having a wall defining a suction chamber;   a crank case forming a crank chamber adjacent an other end of the cylinder block;   a drive shaft rotatably received in the aperture of the cylinder block and extending through the crank chamber;   a swash plate assembly rotatably coupled to the drive shaft, the swash plate assembly operably coupled to the pistons to cause a reciprocating motion thereof;   a rotary valve coupled to the drive shaft and configured to selectively permit fluid communication between the suction chamber of the rear head and the cylinders of the cylinder block; and   a seal disposed adjacent the rotary valve and engaging at least a portion of the wall defining the suction chamber.   
     
     
         9 . The variable displacement compressor of  claim 8 , wherein the seal engages a surface of the rotary valve. 
     
     
         10 . The variable displacement compressor of  claim 8 , wherein the wall defining the suction chamber urges the seal towards the rotary valve. 
     
     
         11 . The variable displacement compressor of  claim 8 , further comprising an urging member disposed adjacent the seal and configured to urge the seal towards the rotary valve, wherein the urging member is one of an o-ring, a spring, and a pressurized gas. 
     
     
         12 . The variable displacement compressor of  claim 8 , wherein the seal has a substantially annular body and a diameter substantially equal to a diameter of an outer surface of the rotary valve. 
     
     
         13 . The variable displacement compressor of  claim 12 , wherein the annular body has a substantially rectangular cross-sectional shape. 
     
     
         14 . The variable displacement compressor of  claim 8 , wherein the seal includes an outer surface having a bevel formed therein, the bevel engaging the wall forming the suction chamber. 
     
     
         15 . The variable displacement compressor of  claim 14 , wherein the bevel has a bevel angle about 70 degrees. 
     
     
         16 . The variable displacement compressor of  claim 8 , further comprising at least one position tab extending laterally outwardly from an outer surface of the seal. 
     
     
         17 . The variable displacement compressor of  claim 16 , wherein the position tab cooperates with the wall forming the suction chamber to militate against a rotational movement of the seal. 
     
     
         18 . The variable displacement compressor of  claim 8 , wherein the seal is formed from a PEEK material. 
     
     
         19 . The variable displacement compressor of  claim 8 , wherein the seal is configured to seal a compressed refrigerant gas path formed intermediate the rotary valve and the wall forming the suction chamber. 
     
     
         20 . A variable displacement compressor, comprising:
 a cylinder block having a plurality of cylinders annularly formed therein and a centrally formed aperture, a plurality of pistons received within the cylinders;   a rear head disposed adjacent one end of the cylinder block, the rear head having a wall defining a suction chamber;   a crank case forming a crank chamber adjacent an other end of the cylinder block;   a drive shaft rotatably received in the aperture of the cylinder block and extending through the crank chamber;   a swash plate assembly rotatably coupled to the drive shaft, the swash plate assembly operably coupled to the pistons to cause a reciprocating motion thereof;   a rotary valve coupled to the drive shaft and configured to selectively permit fluid communication between the suction chamber of the rear head and the cylinders of the cylinder block; and   a seal disposed adjacent the rotary valve and having a bevel formed on an outer surface thereof, the bevel engaging the wall of the rear head forming the suction chamber.